The evolution of phenotypic variation in replicated ecological landscapes

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My research program focuses on studying evolutionary processes influencing morphological and genetical variation within and among populations. The majority of this research occurs on Haida Gwaii and adjacent archipelago and is directed at studies of the 125 lake populations of threespine stickleback which exhibit a remarkable variability in body form. This proposal develops 5 separate MSc projects. (1) understanding the ancestry and relatedness of the highly atypical Giant Stickleback found in six disjunct lakes using genetic markers (2) investigating whether the frequent morphological asymmetries in the defense armour observed in these stickleback populations are associated with lateralized (asymmetric) behaviors, as has been recently reported in other fishes such as guppies which prefer to view threatening stimuli with their left eye but benign stimuli with their right eye. (3) investigating an experimental population of armored stickleback that was established in 1992 in a pond without predatory fish or predatory birds and test the hypothesis that macroinvertebrate piscivores are a selective pressure that leads to armor loss, (4) examining whether there has been evolution of behavioral differences (foraging, defense) between the experimental and ancestral populations and (5) analyzing stable isotope signatures of muscle tissues of stickleback collected from Boulton Lake, Haida Gwaii over the last 30 years to test whether different defense phenotypes occupy different niches. Carbon and stable isotopes provide a time-integrated signature of an individual's niche including habitat and diet. Evidence for a coupling between defense phenotype and isotopic signature would be a very exciting as it would provide an ecological context to morphological variability within populations. This represents one of the major areas of ambiguity and discussion in the evolutionary literature and consequently, this project could be of considerable impact.